U.S. patent application number 17/420172 was filed with the patent office on 2022-03-24 for vehicle drive device.
This patent application is currently assigned to AISIN CORPORATION. The applicant listed for this patent is AISIN CORPORATION. Invention is credited to Takahiro SUZUKI, Tadaaki WATANABE.
Application Number | 20220089013 17/420172 |
Document ID | / |
Family ID | |
Filed Date | 2022-03-24 |
United States Patent
Application |
20220089013 |
Kind Code |
A1 |
SUZUKI; Takahiro ; et
al. |
March 24, 2022 |
VEHICLE DRIVE DEVICE
Abstract
An apparatus including a transmission mechanism in a power
transfer path between a drive source and wheels; an oil pressure
control device supplying lubricating oil to the transmission
mechanism; and a control part outputting an electrical instruction
to increase a flow rate of the supplied lubricating. When the
control part outputs an electrical instruction to the oil pressure
control device to increase a flow rate of lubricating oil supplied
to the transmission mechanism, and determines that the flow rate of
lubricating oil supplied to the transmission mechanism from the oil
pressure control device does not increase as indicated by the
electrical instruction (time t1), the control part considers that
the oil pressure control device is in an abnormal state, and can
impose a limitation that an absolute value of torque of the
transmission mechanism transferred between the wheels and the drive
source be reduced (time t1-t5).
Inventors: |
SUZUKI; Takahiro;
(Kariya-shi, Aichi-ken, JP) ; WATANABE; Tadaaki;
(Kariya-shi, Aichi-ken, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
AISIN CORPORATION |
Kariya, Aichi |
|
JP |
|
|
Assignee: |
AISIN CORPORATION
Kariya, Aichi
JP
|
Appl. No.: |
17/420172 |
Filed: |
January 30, 2020 |
PCT Filed: |
January 30, 2020 |
PCT NO: |
PCT/JP2020/003451 |
371 Date: |
July 1, 2021 |
International
Class: |
B60K 6/48 20060101
B60K006/48; B60K 6/52 20060101 B60K006/52; B60W 10/08 20060101
B60W010/08; B60L 7/26 20060101 B60L007/26; B60W 30/18 20060101
B60W030/18 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 30, 2019 |
JP |
2019-014891 |
Claims
1. A vehicle drive device comprising: a transfer mechanism
interposed in a power transfer path between a drive source and
wheels; an oil pressure supplying part that can supply lubricating
oil to the transfer mechanism; and a control part that can output
an electrical instruction to the oil pressure supplying part to
increase a flow rate of lubricating oil supplied to the transfer
mechanism, wherein when the control part outputs an electrical
instruction to the oil pressure supplying part to increase a flow
rate of lubricating oil supplied to the transfer mechanism, and
determines that a flow rate of lubricating oil supplied to the
transfer mechanism from the oil pressure supplying part does not
increase as indicated by the electrical instruction, the control
part considers that the oil pressure supplying part is in an
abnormal state, and can impose a limitation that an absolute value
of torque of the transfer mechanism transferred between the wheels
and the drive source be reduced.
2. The vehicle drive device according to claim 1, wherein when the
oil pressure supplying part is in the abnormal state, the control
part can impose a limitation that an absolute value of negative
torque of the transfer mechanism transferred to the drive source
from the wheels be reduced.
3. The vehicle drive device according to claim 2, wherein the
control part can output an electrical instruction to the oil
pressure supplying part to selectively perform a first supply mode
in which a flow rate of lubricating oil supplied to the transfer
mechanism from the oil pressure supplying part is a first flow rate
and a second supply mode in which a flow rate supplied to the
transfer mechanism from the oil pressure supplying part is
increased to a second flow rate higher than the first flow rate,
and when the control part outputs an electrical instruction to the
oil pressure supplying part while the first supply mode is
performed, to switch and perform the second supply mode, and
determines that the oil pressure supplying part is not switched to
the second supply mode, the control part considers that the oil
pressure supplying part is in the abnormal state, and can impose a
limitation that an absolute value of the negative torque of the
transfer mechanism be reduced.
4. The vehicle drive device according to claim 2, wherein the
control part can impose a limitation that an absolute value of the
negative torque of the transfer mechanism be reduced, by reducing a
torque load on the drive source.
5. The vehicle drive device according to claim 2, comprising a
rotating electrical machine provided in a power transfer path
between an output shaft of an engine and an input member of the
transfer mechanism, and having a rotating shaft drive-coupled to
the input member of the transfer mechanism, the rotating electrical
machine serving as the drive source, wherein the control part can
impose a limitation that an absolute value of the negative torque
of the transfer mechanism be reduced, by controlling at least one
of regeneration torque of the rotating electrical machine and
output torque of the engine.
6. The vehicle drive device according to claim 2, wherein the
control part sets a negative torque limiting value and reduces the
negative torque limiting value at a predetermined gradient when the
control part starts a limitation that an absolute value of the
negative torque of the transfer mechanism be reduced, the negative
torque limiting value being a limiting value that limits an
absolute value of the negative torque.
7. The vehicle drive device according to claim 2, wherein in a
state in which the control part determines that the oil pressure
supplying part is in the abnormal state, when the control part
outputs an electrical instruction to the oil pressure supplying
part to increase a flow rate of lubricating oil supplied to the
transfer mechanism, and determines that a flow rate of lubricating
oil supplied to the transfer mechanism from the oil pressure
supplying part has increased as indicated by the electrical
instruction, the control part considers that the oil pressure
supplying part has been switched from the abnormal state to a
normal state, and can cancel a limitation that an absolute value of
negative torque of the transfer mechanism be reduced.
8. The vehicle drive device according to claim 7, wherein the
control part sets a negative torque limiting value and increases
the negative torque limiting value at a predetermined gradient when
the control part cancels a limitation that an absolute value of the
negative torque of the transfer mechanism be reduced, the negative
torque limiting value being a limiting value that limits an
absolute value of the negative torque.
9. The vehicle drive device according to claim 2, wherein when the
control part imposes a limitation that an absolute value of the
negative torque of the transfer mechanism be reduced, the control
part outputs an electrical instruction to a brake mechanism that
can brake the wheels, to compensate for a braking force that
decelerates a vehicle and that is reduced by imposing the
limitation, by increasing a braking force of the brake
mechanism.
10. The vehicle drive device according to claim 3, wherein the
control part can impose a limitation that an absolute value of the
negative torque of the transfer mechanism be reduced, by reducing a
torque load on the drive source.
11. The vehicle drive device according to claim 3, comprising a
rotating electrical machine provided in a power transfer path
between an output shaft of an engine and an input member of the
transfer mechanism, and having a rotating shaft drive-coupled to
the input member of the transfer mechanism, the rotating electrical
machine serving as the drive source, wherein the control part can
impose a limitation that an absolute value of the negative torque
of the transfer mechanism be reduced, by controlling at least one
of regeneration torque of the rotating electrical machine and
output torque of the engine.
12. The vehicle drive device according to claim 3, wherein the
control part sets a negative torque limiting value and reduces the
negative torque limiting value at a predetermined gradient when the
control part starts a limitation that an absolute value of the
negative torque of the transfer mechanism be reduced, the negative
torque limiting value being a limiting value that limits an
absolute value of the negative torque.
13. The vehicle drive device according to claim 3, wherein in a
state in which the control part determines that the oil pressure
supplying part is in the abnormal state, when the control part
outputs an electrical instruction to the oil pressure supplying
part to increase a flow rate of lubricating oil supplied to the
transfer mechanism, and determines that a flow rate of lubricating
oil supplied to the transfer mechanism from the oil pressure
supplying part has increased as indicated by the electrical
instruction, the control part considers that the oil pressure
supplying part has been switched from the abnormal state to a
normal state, and can cancel a limitation that an absolute value of
negative torque of the transfer mechanism be reduced.
14. The vehicle drive device according to claim 13, wherein the
control part sets a negative torque limiting value and increases
the negative torque limiting value at a predetermined gradient when
the control part cancels a limitation that an absolute value of the
negative torque of the transfer mechanism be reduced, the negative
torque limiting value being a limiting value that limits an
absolute value of the negative torque.
15. The vehicle drive device according to claim 3, wherein when the
control part imposes a limitation that an absolute value of the
negative torque of the transfer mechanism be reduced, the control
part outputs an electrical instruction to a brake mechanism that
can brake the wheels, to compensate for a braking force that
decelerates a vehicle and that is reduced by imposing the
limitation, by increasing a braking force of the brake
mechanism.
16. The vehicle drive device according to claim 4, comprising a
rotating electrical machine provided in a power transfer path
between an output shaft of an engine and an input member of the
transfer mechanism, and having a rotating shaft drive-coupled to
the input member of the transfer mechanism, the rotating electrical
machine serving as the drive source, wherein the control part can
impose a limitation that an absolute value of the negative torque
of the transfer mechanism be reduced, by controlling at least one
of regeneration torque of the rotating electrical machine and
output torque of the engine.
17. The vehicle drive device according to claim 4, wherein the
control part sets a negative torque limiting value and reduces the
negative torque limiting value at a predetermined gradient when the
control part starts a limitation that an absolute value of the
negative torque of the transfer mechanism be reduced, the negative
torque limiting value being a limiting value that limits an
absolute value of the negative torque.
18. The vehicle drive device according to claim 4, wherein in a
state in which the control part determines that the oil pressure
supplying part is in the abnormal state, when the control part
outputs an electrical instruction to the oil pressure supplying
part to increase a flow rate of lubricating oil supplied to the
transfer mechanism, and determines that a flow rate of lubricating
oil supplied to the transfer mechanism from the oil pressure
supplying part has increased as indicated by the electrical
instruction, the control part considers that the oil pressure
supplying part has been switched from the abnormal state to a
normal state, and can cancel a limitation that an absolute value of
negative torque of the transfer mechanism be reduced.
19. The vehicle drive device according to claim 18, wherein the
control part sets a negative torque limiting value and increases
the negative torque limiting value at a predetermined gradient when
the control part cancels a limitation that an absolute value of the
negative torque of the transfer mechanism be reduced, the negative
torque limiting value being a limiting value that limits an
absolute value of the negative torque.
20. The vehicle drive device according to claim 4, wherein when the
control part imposes a limitation that an absolute value of the
negative torque of the transfer mechanism be reduced, the control
part outputs an electrical instruction to a brake mechanism that
can brake the wheels, to compensate for a braking force that
decelerates a vehicle and that is reduced by imposing the
limitation, by increasing a braking force of the brake mechanism.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a National Stage of International
Application No. PCT/JP2020/003451 filed Jan. 30, 2020, which claims
priority under U.S.C. .sctn. 119(a) to Japanese Patent Application
No. JP2019-014891 filed on Jan. 30, 2019.
TECHNICAL FIELD
[0002] The technique relates to a vehicle drive device mounted on a
vehicle, e.g., an automobile.
BACKGROUND ART
[0003] Conventionally, vehicles such as automobiles having mounted
thereon a vehicle drive device including a transmission mechanism,
etc., have been widely used. A transfer mechanism such as a
transmission mechanism used in such a vehicle drive device may
include, for example, moving parts such as a planetary gear and a
transmission planetary gear unit. Since such moving parts generate
heat during traveling, oil pressure generated by an oil pump is
supplied as lubricating oil to the moving parts from an oil
pressure control device to lubricate and cool the moving parts.
[0004] There is known a vehicle drive device including an oil
pressure control device that can switch the amount of lubricating
oil supplied to a transfer mechanism from the oil pressure control
device between a high flow rate and a low flow rate depending on
timing because heat generated by the transfer mechanism is, for
example, large upon changing gears and smaller upon steady
traveling in which gear changes are not performed than upon
changing gears (see, for example, Patent Literature 1). In the
vehicle drive device, for example, when heat generated by the
transfer mechanism is large, the amount of lubricating oil supplied
to the transfer mechanism from the oil pressure control device is
switched to a high flow rate to prevent overheating, and when heat
generated by the transfer mechanism is small, the supplied amount
is switched to a low flow rate to achieve an improvement in gas
mileage.
CITATIONS LIST
Patent Literature
[0005] Patent Literature 1: JP 2018-146019 A
SUMMARY OF THE DISCLOSURE
Technical Problems
[0006] However, in the vehicle drive device described in Patent
Literature 1, upon switching the amount of lubricating oil supplied
from the oil pressure control device from a low flow rate to a high
flow rate to deal with an increase in the amount of heat generated
by the transfer mechanism, for example, due to sticking in a signal
solenoid valve or a switching valve, there is a possibility that
the amount of lubricating oil supplied may be fixed at the low flow
rate. In this case, despite the increase in the amount of heat
generated by the transfer mechanism, the amount of lubricating oil
supplied remains at the low flow rate, and thus, the transfer
mechanism may go into an overheating state.
[0007] Thus, the present disclosure provides a vehicle drive device
capable of preventing overheating of a transfer mechanism even if
an abnormal state in which the amount of lubricating oil supplied
to the transfer mechanism does not increase to a desired supplied
amount occurs upon increasing the amount of lubricating oil
supplied to the transfer mechanism to deal with an increase in the
amount of heat generated by the transfer mechanism.
Solutions to Problems
[0008] The present vehicle drive device includes a transfer
mechanism interposed in a power transfer path between a drive
source and wheels; an oil pressure supplying part that can supply
lubricating oil to the transfer mechanism; and a control part that
can output an electrical instruction to the oil pressure supplying
part to increase a flow rate of lubricating oil supplied to the
transfer mechanism, and when the control part outputs an electrical
instruction to the oil pressure supplying part to increase a flow
rate of lubricating oil supplied to the transfer mechanism, and
determines that a flow rate of lubricating oil supplied to the
transfer mechanism from the oil pressure supplying part does not
increase as indicated by the electrical instruction, the control
part considers that the oil pressure supplying part is in an
abnormal state, and can impose a limitation that an absolute value
of torque of the transfer mechanism transferred between the wheels
and the drive source be reduced.
Advantageous Effects of Various Aspects of the Disclosure
[0009] According to the present vehicle drive device, upon
increasing the amount of lubricating oil supplied to the transfer
mechanism to deal with an increase in the amount of heat generated
by the transfer mechanism, even if an abnormal state occurs in
which the amount of lubricating oil supplied to the transfer
mechanism does not increase to a desired supplied amount,
overheating of the transfer mechanism can be prevented.
BRIEF DESCRIPTION OF DRAWINGS
[0010] FIG. 1 is skeleton diagram showing a hybrid vehicle
according to an embodiment.
[0011] FIG. 2 is a hydraulic circuit diagram showing a part of an
oil pressure control device of the hybrid vehicle according to the
embodiment.
[0012] FIG. 3 is a control block diagram showing connections of an
ECU of the hybrid vehicle according to the embodiment.
[0013] FIG. 4 is a time chart showing operation of the hybrid
vehicle according to the embodiment.
DESCRIPTION OF EMBODIMENTS
[0014] An embodiment of a hybrid vehicle 100 according to the
present disclosure will be described below based on FIGS. 1 to 4.
In the present embodiment, the term "drive-coupled" refers to a
state in which rotating elements are coupled together such that
they can transfer drive power, and is used as a concept including a
state in which the rotating elements are coupled together such that
they rotate together, or a state in which the rotating elements are
coupled together such that they can transfer drive power through a
clutch, etc.
[0015] As shown in FIG. 1, the hybrid vehicle 100 includes an
engine (E/G) 2 which is an example of a drive source and a hybrid
drive device (vehicle drive device) 3 connected to an output shaft
2a of the engine 2, as a drive system of left and right front
wheels (wheels) 11, and includes a rear motor (M/G) 20 as a drive
system of left and right rear wheels 12. By this, it is configured
such that the front wheels 11 can perform hybrid traveling of a
so-called single-motor parallel system, and the rear wheels 12 can
perform EV traveling, and by simultaneously driving the front
wheels 11 and the rear wheels 12, four-wheel drive is also
possible. Note that although the present embodiment describes a
case in which the hybrid vehicle 100 includes the rear motor 20
that can drive the rear wheels 12, the configuration is not limited
thereto, and the hybrid vehicle 100 may not include the rear motor
20.
[0016] First, the drive system of the front wheels 11 will be
described. An output shaft 5b of the hybrid drive device 3 is
drive-coupled to a differential device which is not shown, and
drive power is transferred to the left and right front wheels 11
from the differential device through left and right drive shafts
11a. The engine rotational speed Ne and engine torque Te of the
engine 2 are freely controlled based on instructions from an ECU 7
which will be described later. In addition, on an exterior side of
the output shaft 2a of the engine 2 there is provided an engine
rotational speed sensor 41 that detects the rotational speed of the
output shaft 2a, i.e., engine rotational speed Ne.
[0017] The hybrid drive device 3 is configured to roughly include a
clutch SSC for engine connection, a motor/generator (M/G, a drive
source, and a rotating electrical machine) 4, a transmission
mechanism (A/T and a transfer mechanism) 5, and the ECU (control
part) 7 that controls these components. The clutch SSC is
interposed between the output shaft 2a of the engine 2 and a rotor
shaft (rotating shaft) 4a of the motor/generator (hereinafter,
simply referred to as "motor") 4, and can provide friction
engagement therebetween. Namely, the clutch SSC is interposed
between the output shaft 2a of the engine 2 and an input shaft 5a
of the transmission mechanism 5, and is provided so as to be able
to connect and disconnect power transfer therebetween. Based on an
instruction from the ECU 7, the engagement state of the clutch SSC
is freely controlled according to clutch oil pressure P.sub.SSC
supplied from an oil pressure control device (V/B) 6, and the
torque capacity of the clutch SSC is also freely controlled.
[0018] The motor 4 is provided in a power transfer path between the
clutch SSC and the input shaft 5a of the transmission mechanism 5,
i.e., between the output shaft 2a of the engine 2 and the input
shaft 5a of the transmission mechanism 5. The motor 4 includes a
stator and a rotor whose depiction is omitted, and the rotor shaft
4a having the rotor connected thereto is drive-coupled to an output
side of the clutch SSC. The motor rotational speed Nm and motor
torque Tm (torque outputted from the motor 4) of the motor 4 are
freely controlled based on instructions from the ECU 7. In
addition, on an exterior side of the rotor shaft 4a of the motor 4
there is provided a motor rotational speed sensor 42 that detects
the rotational speed of the rotor shaft 4a, i.e., motor rotational
speed Nm. The rotor shaft 4a is directly drive-coupled to the input
shaft 5a of the transmission mechanism 5.
[0019] The motor 4 is connected to a battery 23 through an inverter
22. By this, electric power outputted from the battery 23 is fed to
the motor 4 through the inverter 22, by which the motor 4 is
driven. In addition, by idling the motor 4 upon traveling using the
engine 2 or upon coasting, electric power is generated and can be
charged to the battery 23.
[0020] The transmission mechanism 5 is interposed in a power
transfer path between the engine 2 and the front wheels 11, and
includes the input shaft (input member) 5a driven by the engine 2
and the output shaft 5b drive-coupled to the front wheels 11, and
can change the gear ratio between the input shaft 5a and the output
shaft 5b. The transmission mechanism 5 is composed of, for example,
a stepped transmission having moving parts (not shown) such as a
planetary gear and a transmission planetary gear unit, and is
configured to change the gear ratio by changing a transfer path by
changing the friction engagement states of a plurality of friction
engagement elements (clutches and a brake) based on oil pressure
supplied from the oil pressure control device 6. In addition, the
transmission mechanism 5 includes a lubricating oil passage (LUBE)
5L (see FIG. 2). Lubricating oil supplied to the lubricating oil
passage 5L from the oil pressure control device 6 lubricates and
cools the moving parts such as the planetary gear and the
transmission planetary gear unit of the transmission mechanism
5.
[0021] As some of the plurality of friction engagement elements,
the transmission mechanism 5 includes a first clutch C1 and a
second clutch, a brake, etc., which are not shown. The first clutch
C1 is configured to freely connect and disconnect power transfer
between the input shaft 5a and the output shaft 5b, and can provide
friction engagement by switching between a disengaged state, a
slip-engaged state, and a completely engaged state. Based on an
instruction from the ECU 7, the engagement state of the first
clutch C1 is freely controlled according to first clutch oil
pressure P.sub.C1 supplied from the oil pressure control device 6,
and the torque capacity of the first clutch C1 is also freely
controlled.
[0022] In addition, on an exterior side of the input shaft 5a of
the transmission mechanism 5 there is provided an input rotational
speed sensor 43 that detects the rotational speed of the input
shaft 5a, i.e., input rotational speed (in the present embodiment,
the same as the motor rotational speed Nm). Furthermore, on an
exterior side of the output shaft 5b of the transmission mechanism
5 there is provided an output rotational speed sensor 44 that
detects the rotational speed of the output shaft 5b, i.e., output
rotational speed Nout. Since the output shaft 5b is, as described
above, drive-coupled to the front wheels 11 through the
differential device, etc., the output rotational speed sensor 44
can also be used to detect vehicle speed V.
[0023] Note that in the present embodiment, description is made
assuming that the first clutch C1 attains first forward gear by,
for example, going into an engaged state with a one-way clutch
which is not shown, i.e., first forward gear of the transmission
mechanism 5 is attained by only one first clutch C1 being engaged.
Note, however, that the configuration is not limited thereto, and
for example, the first clutch C1 may attain a shift speed that
allows the hybrid vehicle 100 to start, such as first forward gear
or third forward gear, by being simultaneously engaged with another
friction engagement element.
[0024] In addition, although in the present embodiment description
is made assuming that the transmission mechanism 5 is a stepped
transmission, the transmission mechanism 5 may be, for example, a
belt, toroidal, or cone-ring continuously variable transmission,
and in that case, the first clutch C1 can be considered to be a
clutch that is included in the continuously variable transmission
and can connect and disconnect power transfer.
[0025] In addition, the above-described clutch SSC and first clutch
C1 are friction-engageable elements whose transferable torque
capacity can vary in magnitude depending on the magnitude of oil
pressure that presses two or more friction engagement members, and
are normally configured to include a piston that presses the
friction engagement members, a hydraulic cylinder that presses the
piston, and a return spring that acts in an opposite direction to
the hydraulic cylinder. Note, however, that the configuration is
not limited thereto, and it may be structured such that a piston is
driven by differential pressure between opposed cylinders or it may
be structured such that the friction engagement members are pressed
by, for example, an arm that is allowed to move by a hydraulic
actuator. Note that although the present embodiment describes a
case in which the clutch SSC, the first clutch C1, etc., are
hydraulically controlled friction engagement elements, the
configuration is not limited thereto, and for example,
electromagnetic clutches may be applied.
[0026] The states of the clutch SSC and the first clutch C1 are, as
described above, controlled by the magnitude of oil pressure, and
are classified into a "disengaged state" in which the friction
engagement members are separated from each other, a "slip-engaged
state" in which torque capacity to be transferred is generated
while slipping, and a "completely engaged state" in which the
friction engagement members are fastened together by increasing oil
pressure as much as possible. Note that the "slip-engaged state"
can be defined to be a period from when the piston strokes after
the disengaged state and reaches a stroke end where the piston
comes into contact with the friction engagement members until the
rotational speeds of the friction engagement members are
synchronized with each other, and the "disengaged state" can be
defined to be a state in which the piston is less than the stroke
end and is separated from the friction engagement members.
[0027] In addition, the hybrid drive device 3 includes a mechanical
oil pump (MO/P) 30 (see FIG. 2); and a motor-driven oil pump (EO/P)
31 (see FIG. 2) whose amount of discharge can be controlled by an
electrical signal. The mechanical oil pump 30 is provided on a
transfer shaft disposed parallel to the input shaft 5a of the
transmission mechanism 5. The mechanical oil pump 30 is connected
to the input shaft 5a by a chain, etc., and is driven by power of
the input shaft 5a transferred thereto through the transfer shaft.
The motor-driven oil pump 31 is driven independently of the
mechanical oil pump 30, by a motor different from the engine 2 and
the motor 4.
[0028] As shown in FIG. 2, the oil pressure control device 6 is
composed of, for example, a valve body and includes a regulator
valve 32 that regulates oil pressure from the mechanical oil pump
30 or the motor-driven oil pump 31 into line pressure PL based on a
control signal from the ECU 7; a flow rate switching valve 35 that
can supply lubricating oil to the lubricating oil passage 5L of the
transmission mechanism 5 and is used to switch the amount of
lubricating oil supplied; and a signal solenoid valve SR that can
supply signal pressure PSR that switches the flow rate switching
valve 35. In addition, the oil pressure control device 6 includes
linear solenoid valves for supplying and exhausting oil pressure
to/from the first clutch C1, the clutch SSC, a motor-disconnecting
clutch CM which will be described later, and each of other
engagement elements based on control signals from the ECU 7, and
can supply and exhaust oil pressure to/from each engagement
element.
[0029] The regulator valve 32 includes a spool (not shown) biased
by a spring 32s, and includes, at one end of the spool, a feedback
port 32a, a line pressure port 32b, and a backpressure port 32c.
Control pressure PSLT from a linear solenoid valve that is
controlled based on the throttle position is supplied to an oil
chamber in which the spring 32s is disposed. Oil from the
mechanical oil pump 30 is supplied to the feedback port 32a and the
line pressure port 32b via a check valve 33 and through a line
pressure oil passage al, and the spool is allowed to move by
feedback pressure of the feedback port 32a and the control pressure
PSLT of the oil chamber to adjust a communication rate between the
line pressure port 32b and the backpressure port 32c, by which the
line pressure port 32b is regulated to line pressure PL determined
based on the throttle position. Lubricating oil pressure P1 from
the backpressure port 32c communicates with an oil passage b1. The
check valve 33 allows the flow of oil pressure PMOP from the
mechanical oil pump 30 to the regulator valve 32 and restricts the
flow of oil pressure to an opposite side.
[0030] In addition, the motor-driven oil pump 31 is connected to
the line pressure oil passage al via a check valve 34. The check
valve 34 is interposed between the mechanical oil pump 30 and the
motor-driven oil pump 31, and allows the flow of oil pressure PEOP
from the motor-driven oil pump 31 to the regulator valve 32 and
restricts the flow of oil pressure to an opposite side.
[0031] The flow rate switching valve 35 is a spool valve including
a spool which is not shown and a spring 35s, and switches oil
pressure to be outputted, by movement of the spool according to a
relationship between signal pressure PSR supplied from the signal
solenoid valve SR and the biasing force of the spring 35s. The flow
rate switching valve 35 includes a hydraulic oil chamber 35a for
providing a pressing force in a direction in which the spool is
switched by the signal pressure PSR; an input port 35b to which the
lubricating oil pressure P1 is inputted from the oil passage b1; an
output port 35c connected to the lubricating oil passage 5L through
an oil passage b2; an interruption port 35d; and the like. In
addition, the oil passage b2 is provided with an oil pressure
switch (PSW) 36.
[0032] The signal solenoid valve SR is, for example, a normally
closed solenoid valve, and includes an input port SRa to which
modulator pressure Pmod is supplied; and an output port SRb
connected to the hydraulic oil chamber 35a of the flow rate
switching valve 35, and is controlled by the ECU 7 to generate
signal pressure PSR based on the modulator pressure Pmod and supply
and exhaust the signal pressure PSR to/from the hydraulic oil
chamber 35a. Note that although the present embodiment describes a
case in which the oil pressure switch 36 is provided in the oil
passage b2, the configuration is not limited thereto. For example,
the oil pressure switch 36 may be provided as an oil pressure
sensor in an oil passage between the output port SRb of the signal
solenoid valve SR and the hydraulic oil chamber 35a of the flow
rate switching valve 35, instead of in the oil passage b2.
[0033] When the signal solenoid valve SR is in an off state and
signal pressure PSR is not outputted from the output port SRb, in
the flow rate switching valve 35, the input port 35b communicates
with the output port 35c, and lubricating oil pressure P1 from the
oil passage b1 is supplied to the lubricating oil passage 5L
through the flow rate switching valve 35. In addition, when the
signal solenoid valve SR is in an on state and signal pressure PSR
is outputted from the output port SRb, in the flow rate switching
valve 35, the input port 35b communicates with the interruption
port 35d, and lubricating oil pressure P1 from the oil passage b1
is not supplied to the lubricating oil passage 5L through the flow
rate switching valve 35.
[0034] Meanwhile, the oil passage b1 is connected to the
lubricating oil passage 5L through an orifice 37 and an oil passage
b3. Hence, lubricating oil pressure P1 from the oil passage b1 is
always supplied to the lubricating oil passage 5L through the oil
passage b3 while the flow rate is reduced by the orifice 37. Thus,
when the signal solenoid valve SR is in an off state, lubricating
oil with a high flow rate is supplied to the lubricating oil
passage 5L from the oil passage b2 and the oil passage b3, and when
the signal solenoid valve SR is in an on state, lubricating oil
with a low flow rate is supplied to the lubricating oil passage 5L
only from the oil passage b3.
[0035] Next, the drive system of the rear wheels 12 will be
described. As shown in FIG. 1, the rear motor 20 is connected to
the battery 23 through an inverter 24, and is configured to be
driven and regenerate freely by the inverter 24 controlling
electric power thereof based on a drive instruction from the ECU 7.
The rear motor 20 is drive-coupled to a gearbox 21 through the
motor-disconnecting clutch CM. The gearbox 21 includes a reduction
gear mechanism with a predetermined reduction ratio and a
differential device which are not shown. Upon engagement of the
gearbox 21 with the motor-disconnecting clutch CM, the gearbox 21
transfers rotation of the rear motor 20 to the left and right rear
wheels 12 while reducing the speed of the rotation by the reduction
gear mechanism in the gearbox 21 and absorbing differential
rotation between left and right axles 12a by the differential
device.
[0036] At least one of a pair of the front wheels 11 and a pair of
the rear wheels 12 is provided with a brake mechanism 13 (see FIG.
3). In the present embodiment, the brake mechanism 13 is provided
on both the front wheels 11 and the rear wheels 12. The brake
mechanisms 13 are connected to the oil pressure control device 6
and driven by an operation on a brake pedal, and other than an
operation on the brake pedal, by a determination made by the ECU 7
depending on a situation, oil pressure is supplied from the oil
pressure control device 6, by which the brake mechanisms 13 can
brake the front wheels 11 and the rear wheels 12.
[0037] As shown in FIG. 3, the ECU 7 includes, for example, a CPU
71, a ROM 72 that stores a processing program, a RAM 73 that
temporarily stores data, and an input and output circuit (I/F) 74,
and outputs various types of electrical instructions such as
control signals to the oil pressure control device 6 and control
signals to the inverters 22 and 24. In order to detect an
engagement state of the clutch SSC, etc., to the ECU 7 there are
connected the engine rotational speed sensor 41 that detects the
rotational speed of the output shaft 2a of the engine 2, the motor
rotational speed sensor 42 that detects the rotational speed of the
rotor shaft 4a of the motor 4, the input rotational speed sensor 43
that detects the rotational speed of the input shaft 5a of the
transmission mechanism 5, the output rotational speed sensor 44
that detects the rotational speed of the output shaft 5b of the
transmission mechanism 5, etc. The ECU 7 freely controls engine
rotational speed Ne and engine torque Te by providing instructions
to the engine 2 through an engine control part which is not shown.
In addition, the ECU 7 freely performs control of motor rotational
speed Nm by rotational speed control or control of motor torque Tm
by torque control, by controlling electric power of the motor 4
through the inverter 22, and freely performs control of motor
rotational speed by rotational speed control or control of motor
torque by torque control, by controlling electric power of the rear
motor 20 through the inverter 24.
[0038] The ECU 7 is connected to the oil pressure control device 6
and can output an electrical instruction to the oil pressure
control device 6 to increase the flow rate of lubricating oil
supplied to the transmission mechanism 5, and can obtain a result
of detection by the oil pressure switch 36. By the ECU 7 outputting
an electrical instruction to supply oil pressure to the brake
mechanisms 13 from the oil pressure control device 6, oil pressure
is supplied to the brake mechanisms 13, by which the front wheels
11 and the rear wheels 12 can be braked.
[0039] In the hybrid vehicle 100 configured in the above-described
manner, as shown in FIG. 1, in traveling using drive power of the
engine 2 and/or the motor 4, power outputted from the hybrid drive
device 3 is transferred to the front wheels 11 and the
motor-disconnecting clutch CM is disengaged, by which the rear
motor 20 goes into a state of being disconnected from the rear
wheels 12. Then, in the transmission mechanism 5, an optimal shift
speed is determined by the ECU 7 according to a shift range,
vehicle speed, and accelerator pedal position, by which the oil
pressure control device 6 is electronically controlled, forming a
shift speed formed based on the transmission determination. In
addition, four-wheel drive can be implemented by driving the rear
motor 20 by engaging the motor-disconnecting clutch CM when power
outputted from the hybrid drive device 3 is transferred to the
front wheels 11.
[0040] In addition, in the hybrid vehicle 100, as shown in FIG. 2,
upon steady traveling with no gear changes, the signal solenoid
valve SR is brought into an on state to allow the input port 35b
and the interruption port 35d of the flow rate switching valve 35
to communicate with each other, by which the connection between the
oil passage b1 and the oil passage b2 is interrupted. By this,
lubricating oil with a low flow rate (first flow rate) is supplied
to the lubricating oil passage 5L only from the oil passage b3
(first supply mode), by which excess flow of lubricating oil is
suppressed and an improvement in gas mileage can be achieved. In
addition, for example, upon changing gears during traveling, since
the moving parts of the transmission mechanism 5 generate more heat
than upon steady traveling, the signal solenoid valve SR is brought
into an off state to allow the input port 35b and the output port
35c of the flow rate switching valve 35 to communicate with each
other, by which the oil passage b1 is connected to the oil passage
b2 and lubricating oil pressure P1 flows through the oil passage
b2. By this, lubricating oil with a high flow rate (second flow
rate) is supplied to the lubricating oil passage 5L from the oil
passage b2 and the oil passage b3 in a joined manner (second supply
mode), by which the moving parts of the transmission mechanism 5
can be sufficiently cooled. Namely, the ECU 7 can output an
electrical instruction to the oil pressure control device 6 to
selectively perform the first supply mode in which the flow rate of
lubricating oil supplied to the transmission mechanism 5 from the
oil pressure control device 6 is a low flow rate and the second
supply mode in which the flow rate supplied to the transmission
mechanism 5 from the oil pressure control device 6 is increased to
a high flow rate.
[0041] Next, operation of each part performed when the hybrid
vehicle 100 of the present embodiment performs, during traveling,
coasting while regeneration is performed by the motor 4 by stopping
the drive of the engine 2 will be described based on a time chart
of FIG. 4. As shown in FIG. 4, at time to, coasting is being
performed while engine braking is working by bringing the clutch
SSC into a completely engaged state to stop the drive of the engine
2, and the motor 4 is not driven and is performing regeneration,
and the motor-disconnecting clutch CM is in a state of being
disengaged.
[0042] At this time, steady traveling with no gear changes is
performed, and since heat generated by the moving parts of the
transmission mechanism 5 is small, the amount of lubricating oil
supplied to the lubricating oil passage 5L of the transmission
mechanism 5 from the oil pressure control device 6 has a low flow
rate.
[0043] In this state, torque of the transmission mechanism 5
transferred to the engine 2 and the motor 4 from the front wheels
11 is negative torque. In the present embodiment, the magnitude of
the negative torque is defined as follows. First, an increase in
the negative torque indicates that the negative torque moves away
from 0, i.e., the negative torque becomes negative. In addition, a
reduction in the negative torque indicates that the negative torque
moves toward 0, i.e., the negative torque becomes positive. Namely,
in the present embodiment, the magnitude of the negative torque has
the same meaning as the magnitude of the absolute value of the
negative torque, and the "magnitude of the negative torque" and the
"absolute value of the negative torque" are interchangeable terms.
The ECU 7 sets, as a negative torque limiting value, a limiting
value that limits the magnitude (absolute value) of the negative
torque so as to prevent the negative torque from getting too large.
At time t0, since heat generated by the moving parts of the
transmission mechanism 5 is small because of steady traveling, even
if the negative torque increases, the possibility of overheating of
the moving parts is small, and thus, the negative torque limiting
value is set to be large, i.e., large toward a negative side.
[0044] In addition, if the negative torque limiting value is
reduced and reaches 0, then it becomes impossible to perform
regeneration by the motor 4 or to use engine braking, and thus, in
order to prevent the negative torque limiting value from becoming
too small and to prevent the negative torque from becoming smaller
than the negative torque limiting value, a negative torque final
limiting value is set to be more on a negative side than 0. Note
that the negative torque final limiting value changes depending on
a traveling state such as vehicle speed.
[0045] In addition, the ECU 7 sets a drive torque required value of
the motor 4 and the engine 2, taking into account vehicle speed,
the amount of operation on an accelerator pedal or a brake pedal, a
transmission state, etc. Furthermore, the ECU 7 sets actual output
torque (actual torque) of the motor 4 and the engine 2 based on the
drive torque required value and the negative torque limiting value.
At time t0, since the drive torque required value is smaller than
the negative torque limiting value, the actual torque is not
limited by the negative torque limiting value, and the drive torque
required value and the actual torque roughly match each other.
[0046] For example, when heat generated by the moving parts of the
transmission mechanism 5 is expected to increase because gear
changes are performed, in order to supply more lubricating oil to
the moving parts, the ECU 7 outputs an electrical instruction to
increase the amount of lubricating oil supplied to the lubricating
oil passage 5L of the transmission mechanism 5 from the oil
pressure control device 6. Here, it is assumed that the signal
solenoid valve SR or the flow rate switching valve 35 has caused
valve sticking and switching of the flow rate switching valve 35 is
not performed, by which lubricating oil pressure P1 does not flow
through the oil passage b2, resulting in an abnormal state in which
the oil pressure switch 36 does not detect oil pressure. In this
case, the ECU 7 determines that despite the ECU 7 outputting an
electrical instruction to output signal pressure PSR from the
signal solenoid valve SR, the oil pressure switch 36 does not
detect oil pressure, and thereby detects occurrence of an abnormal
state in which desired lubricating oil pressure P1 is not outputted
from the oil passage b2, and considers that a failure has occurred,
and sets an abnormal state flag to on (time t1).
[0047] If the amount of heat generated by the moving parts of the
transmission mechanism 5 increases in this state, then the moving
parts are overheated because the amount of lubricating oil supplied
has a low flow rate, and thus, it is not desirable. Hence, in the
present embodiment, at time t1, in order to limit the negative
torque of the transmission mechanism 5, the ECU 7 reduces the
negative torque limiting value to the drive torque required value,
and then gradually reduces the negative torque limiting value at a
predetermined gradient. Note that since the negative torque
limiting value is a negative value, the value is increased in the
sense of the magnitude of the numerical value, and sweep-up is
performed. Namely, when the ECU 7 starts a limitation that the
magnitude of the negative torque of the transmission mechanism 5 be
reduced (time t1), the ECU 7 reduces the negative torque limiting
value at a predetermined gradient. When the negative torque
limiting value reaches the negative torque final limiting value, if
the negative torque limiting value is further reduced, then
regeneration efficiency significantly decreases, and thus, the
reduction in the negative torque limiting value is stopped (time
t2). Thereafter, the negative torque limiting value changes so as
to take the same value as the negative torque final limiting
value.
[0048] On the other hand, when the drive torque required value has
exceeded the negative torque limiting value as a result of the
reduction in the negative torque limiting value by the limitation
on the torque of the transmission mechanism 5, i.e., when the drive
torque required value is more on a negative side than the negative
torque limiting value (time t1-t3), the ECU 7 gradually reduces the
actual torque of the motor 4 and the engine 2 at a predetermined
gradient in accordance with the negative torque limiting value
(time t1-t2), and then allows the actual torque to change in
accordance with the negative torque final limiting value (time
t2-t3). Thereafter, when the drive torque required value has become
smaller than the negative torque limiting value again, i.e., when
the drive torque required value is more on a positive side than the
negative torque limiting value (time t3-), the ECU 7 allows the
actual torque of the motor 4 and the engine 2 to change in
accordance with the drive torque required value.
[0049] In the present embodiment, the ECU 7 changes the actual
torque by controlling regeneration torque by controlling feeding of
the motor 4. Alternatively, the actual torque may be changed, for
example, by controlling torque of the output shaft 2a by valve
control of the engine 2, etc., or by upshifting the shift speed.
Namely, the ECU 7 can impose a limitation that the magnitude of the
negative torque of the transmission mechanism 5 be reduced, by
reducing the torque load on the motor 4 or the engine 2.
Particularly, in the present embodiment, the ECU 7 can impose a
limitation that the magnitude of the negative torque of the
transmission mechanism 5 be reduced, by controlling at least one of
the regeneration torque of the motor 4 and the output torque of the
engine 2.
[0050] Namely, when the ECU 7 outputs an electrical instruction to
the oil pressure control device 6 to increase the flow rate of
lubrication oil supplied to the transmission mechanism 5, and
determines that the flow rate of lubricating oil supplied to the
transmission mechanism 5 from the oil pressure control device 6
does not increase as indicated by the electrical instruction, the
ECU 7 considers that the oil pressure control device 6 is in an
abnormal state, and can impose a limitation that the magnitude of
the negative torque of the transmission mechanism 5 transferred to
the motor 4 and the engine 2 from the front wheels 11 be reduced.
In the present embodiment, when the ECU 7 outputs an electrical
instruction to the oil pressure control device 6 while a first
supply mode is performed, to switch and perform a second supply
mode, and determines that the oil pressure control device 6 is not
switched to the second supply mode, the ECU 7 considers that the
oil pressure control device 6 is in an abnormal state, and can
impose a limitation that the magnitude of the negative torque of
the transmission mechanism 5 be reduced.
[0051] In addition, for example, at time t1-t3, the negative torque
of the transmission mechanism 5 is limited and smaller than that in
a normal state (time t0-t1, etc.), and thus, a braking force that
decelerates the hybrid vehicle 100 is reduced. Hence, it is
desirable to compensate for the reduced braking force. Hence, in
the present embodiment, when the ECU 7 imposes a limitation that
the magnitude of the negative torque of the transmission mechanism
5 be reduced, the ECU 7 outputs an electrical instruction to a
brake mechanism 13 to compensate for a braking force that
decelerates the hybrid vehicle 100 and that is reduced by imposing
the limitation, by increasing a braking force of the brake
mechanism 13.
[0052] In addition, in the present embodiment, it is assumed that
at time t4, the abnormal state in which switching of the flow rate
switching valve 35 is not performed is cancelled for some kind of
reason. A situation in which the abnormal state is canceled
includes, for example, that the flow rate switching valve 35 is
switched while maintaining a request to increase the amount of
lubricating oil supplied to the lubricating oil passage 5L of the
transmission mechanism 5 from the oil pressure control device 6 to
a high flow rate, or that a request to increase the amount of
lubricating oil supplied to the lubricating oil passage 5L of the
transmission mechanism 5 from the oil pressure control device 6 to
a high flow rate is canceled and it is OK to maintain a low flow
rate. In such a case, the ECU 7 sets the abnormal state flag to
off, and after a lapse of a predetermined period of time, at time
t5, the ECU 7 sets a normal state flag to on.
[0053] In addition, in such a case, there is no need to limit the
negative torque of the transmission mechanism 5 to reduce the
negative torque limiting value like at time t1-t5, and in order to
secure a braking force, the limitation on the negative torque is
canceled and the negative torque limiting value is increased (time
t5). Here, the negative torque limiting value is gradually
increased at a predetermined gradient. Note that since the negative
torque limiting value is a negative value, the value is reduced in
the sense of the magnitude of the numerical value, and sweep-down
is performed. Thus, in a state in which the ECU 7 determines that
the oil pressure control device 6 is in an abnormal state (time
t1), when the ECU 7 outputs an electrical instruction to the oil
pressure control device 6 to increase the flow rate of lubricating
oil supplied to the transmission mechanism 5 (time t1-t5), and
determines that the flow rate of lubricating oil supplied to the
transmission mechanism 5 from the oil pressure control device 6 has
increased as indicated by the electrical instruction (time t5), the
ECU 7 considers that the oil pressure control device 6 has been
switched from the abnormal state to a normal state, and can cancel
the limitation that the magnitude of the negative torque of the
transmission mechanism 5 be reduced (time t5-t6). Particularly, in
the present embodiment, when the ECU 7 cancels the limitation that
the magnitude of the negative torque of the transmission mechanism
5 be reduced, the ECU 7 increases the negative torque limiting
value at a predetermined gradient.
[0054] When the negative torque limiting value has increased so as
to be sufficiently away from the drive torque required value,
exceeding a predetermined difference from the drive torque required
value (time t6), it is determined that overheating of the
transmission mechanism 5 does not occur, and the sweep-down is
stopped and the negative torque limiting value is set to be large
in the same manner as at time t0. Then, the hybrid vehicle 100
performs steady traveling.
[0055] As described above, according to the hybrid drive device 3
of the present embodiment, when the ECU 7 outputs an electrical
instruction to the oil pressure control device 6 to increase the
flow rate of lubrication oil supplied to the transmission mechanism
5, and determines that the flow rate of lubricating oil supplied to
the transmission mechanism 5 from the oil pressure control device 6
does not increase as indicated by the electrical instruction, the
ECU 7 considers that the oil pressure control device 6 is in an
abnormal state, and can impose a limitation that the magnitude of
the negative torque of the transmission mechanism 5 be reduced.
Hence, upon increasing the amount of lubricating oil supplied to
the transmission mechanism 5 to deal with an increase in the amount
of heat generated by the transmission mechanism 5, even if an
abnormal state occurs in which the amount of lubricating oil
supplied to the transmission mechanism 5 does not increase to a
desired supplied amount, overheating of the transmission mechanism
5 can be prevented.
[0056] In addition, according to the hybrid drive device 3 of the
present embodiment, when the ECU 7 outputs an electrical
instruction to the oil pressure control device 6 while a first
supply mode is performed, to switch and perform a second supply
mode, and determines that the oil pressure control device 6 is not
switched to the second supply mode, the ECU 7 considers that the
oil pressure control device 6 is in an abnormal state, and can
impose a limitation that the magnitude of the negative torque of
the transmission mechanism 5 be reduced. Hence, in the oil pressure
control device 6 having a first supply mode in which the supplied
amount has a low flow rate and a second supply mode in which the
supplied amount has a high flow rate, upon switching from the first
supply mode to the second supply mode to deal with an increase in
the amount of heat generated by the transmission mechanism 5, even
if an abnormal state occurs in which the oil pressure control
device 6 is not switched to the second supply mode, overheating of
the transmission mechanism 5 can be prevented.
[0057] In addition, according to the hybrid drive device 3 of the
present embodiment, the ECU 7 can impose a limitation that the
magnitude of the negative torque of the transmission mechanism 5 be
reduced, by reducing the torque load on the engine 2 or the motor
4. Particularly, according to the hybrid drive device 3 of the
present embodiment, the ECU 7 can impose a limitation that the
magnitude of the negative torque of the transmission mechanism 5 be
reduced, by controlling at least one of the regeneration torque of
the motor 4 and the output torque of the engine 2. Hence, the ECU 7
can limit the negative torque of the transmission mechanism 5
without accompanying the transmission operation of the transmission
mechanism 5 with large heat generation.
[0058] In addition, according to the hybrid drive device 3 of the
present embodiment, when the ECU 7 starts a limitation that the
magnitude of the negative torque of the transmission mechanism 5 be
reduced, the ECU 7 reduces the negative torque limiting value at a
predetermined gradient. Hence, compared to a case in which the
negative torque limiting value is suddenly reduced, i.e., a case in
which the negative torque limiting value is changed toward a
positive side, a sudden reduction in braking force that decelerates
the hybrid vehicle 100 can be suppressed.
[0059] In addition, according to the hybrid drive device 3 of the
present embodiment, when the ECU 7 determines that after limiting
the negative torque limiting value, an abnormal state of the oil
pressure control device 6 is canceled and the oil pressure control
device 6 goes into a normal state, the ECU 7 can cancel the
limitation that the magnitude of the negative torque of the
transmission mechanism 5 be reduced. Hence, a braking force based
on the engine 2 and the motor 4 is secured again, and driver's
desired traveling can be implemented.
[0060] In addition, according to the hybrid drive device 3 of the
present embodiment, when the ECU 7 cancels the limitation that the
magnitude of the negative torque of the transmission mechanism 5 be
reduced, the ECU 7 increases the negative torque limiting value at
a predetermined gradient. Hence, compared to a case in which the
negative torque limiting value is suddenly increased, i.e., a case
in which the negative torque limiting value is changed toward a
negative side, a sudden increase in braking force that decelerates
the hybrid vehicle 100 can be suppressed.
[0061] In addition, according to the hybrid drive device 3 of the
present embodiment, when the ECU 7 imposes a limitation that the
magnitude of the negative torque of the transmission mechanism 5 be
reduced, the ECU 7 outputs an electrical instruction to a brake
mechanism 13 that can brake the front wheels 11, to compensate for
a braking force that decelerates the hybrid vehicle 100 and that is
reduced by imposing the limitation, by increasing a braking force
of the brake mechanism 13. Hence, a braking force that decelerates
the hybrid vehicle 100 can be compensated for by increasing a
braking force of the brake mechanism 13, and thus, a reduction in
drivability can be suppressed.
[0062] Note that although in the present embodiment described
above, the hybrid drive device 3 is a vehicle drive device mounted
on the hybrid vehicle 100 of a single-motor parallel system, the
configuration is not limited thereto. Any vehicle drive device can
be applied as long as the vehicle drive device includes at least
the transmission mechanism 5 and the oil pressure control device 6,
and can switch a flow rate supplied to the lubricating oil passage
5L of the transmission mechanism 5.
[0063] In addition, although the present embodiment described above
describes a case in which when the ECU 7 imposes a limitation that
the absolute value of negative torque of the transmission mechanism
5 be reduced, the ECU 7 compensates for a braking force that
decelerates the hybrid vehicle 100 and that is reduced by imposing
the limitation, by increasing a braking force of a brake mechanism
13, the configuration is not limited thereto. For example, a
braking force that decelerates may be compensated for by bringing
the motor-disconnecting clutch CM into an engaged state to allow
the rear motor 20 to generate regeneration torque.
[0064] In addition, although the present embodiment described above
describes a case in which when, upon increasing the amount of
lubricating oil supplied to the transmission mechanism 5 to deal
with an increase in the amount of heat generated by the
transmission mechanism 5, an abnormal state has occurred in which
the amount of lubricating oil supplied to the transmission
mechanism 5 does not increase to a desired supplied amount, the ECU
7 imposes a limitation that the absolute value of negative torque
of the transmission mechanism 5 transferred to the engine 2 and the
motor 4 from the front wheels 11 be reduced, the configuration is
not limited thereto. For example, when an abnormal state has
occurred in which the amount of lubricating oil supplied to the
transmission mechanism 5 does not increase to a desired supplied
amount, the ECU 7 may impose a limitation that the absolute value
of positive torque of the transmission mechanism 5 transferred to
the front wheels 11 from the engine 2 and the motor 4 be reduced.
Namely, the ECU 7 can be configured such that when, upon increasing
the amount of lubricating oil supplied to the transmission
mechanism 5 to deal with an increase in the amount of heat
generated by the transmission mechanism 5, an abnormal state has
occurred in which the amount of lubricating oil supplied to the
transmission mechanism 5 does not increase to a desired supplied
amount, the ECU 7 can impose a limitation that the absolute value
of torque of the transmission mechanism 5 transferred between the
front wheels 11 and the engine 2 and the motor 4 be reduced. In
this case, too, overheating of the transmission mechanism 5 can be
prevented.
[0065] Note that the present embodiment includes at least the
following configurations. A vehicle drive device (3) of the present
embodiment includes a transfer mechanism (5) interposed in a power
transfer path between a drive source (2, 4) and wheels (11); an oil
pressure supplying part (6) that can supply lubricating oil to the
transfer mechanism (5); and a control part (7) that can output an
electrical instruction to the oil pressure supplying part (6) to
increase a flow rate of lubricating oil supplied to the transfer
mechanism (5), and when the control part (7) outputs an electrical
instruction to the oil pressure supplying part (6) to increase a
flow rate of lubricating oil supplied to the transfer mechanism
(5), and determines that a flow rate of lubricating oil supplied to
the transfer mechanism (5) from the oil pressure supplying part (6)
does not increase as indicated by the electrical instruction, the
control part (7) considers that the oil pressure supplying part (6)
is in an abnormal state, and can impose a limitation that an
absolute value of torque of the transfer mechanism (5) transferred
between the wheels (11) and the drive source (2, 4) be reduced.
[0066] According to this configuration, upon increasing the amount
of lubricating oil supplied to the transfer mechanism (5) to deal
with an increase in the amount of heat generated by the transfer
mechanism (5), even if an abnormal state occurs in which the amount
of lubricating oil supplied to the transfer mechanism (5) does not
increase to a desired supplied amount, overheating of the transfer
mechanism (5) can be prevented.
[0067] In addition, in the vehicle drive device (3) of the present
embodiment, when the oil pressure supplying part (6) is in the
abnormal state, the control part (7) can impose a limitation that
an absolute value of negative torque of the transfer mechanism (5)
transferred to the drive source (2, 4) from the wheels (11) be
reduced. According to this configuration, upon transferring torque
to the drive source (2, 4) from the wheels (11), even if an
abnormal state occurs in which the amount of lubricating oil
supplied does not increase to a desired supplied amount,
overheating of the transfer mechanism (5) can be prevented.
[0068] In addition, in the vehicle drive device (3) of the present
embodiment, the control part (7) can output an electrical
instruction to the oil pressure supplying part (6) to selectively
perform a first supply mode in which a flow rate of lubricating oil
supplied to the transfer mechanism (5) from the oil pressure
supplying part (6) is a first flow rate and a second supply mode in
which a flow rate supplied to the transfer mechanism (5) from the
oil pressure supplying part (6) is increased to a second flow rate
higher than the first flow rate, and when the control part (7)
outputs an electrical instruction to the oil pressure supplying
part (6) while the first supply mode is performed, to switch and
perform the second supply mode, and determines that the oil
pressure supplying part (6) is not switched to the second supply
mode, the control part (7) considers that the oil pressure
supplying part (6) is in the abnormal state, and can impose a
limitation that an absolute value of the negative torque of the
transfer mechanism (5) be reduced.
[0069] According to this configuration, in the oil pressure
supplying part (6) having the first supply mode in which the
supplied amount has a low flow rate and the second supply mode in
which the supplied amount has a high flow rate, upon switching from
the first supply mode to the second supply mode to deal with an
increase in the amount of heat generated by the transfer mechanism
(5), even if an abnormal state occurs in which the oil pressure
supplying part (6) is not switched to the second supply mode,
overheating of the transfer mechanism (5) can be prevented.
[0070] In addition, in the vehicle drive device (3) of the present
embodiment, the control part (7) can impose a limitation that an
absolute value of the negative torque of the transfer mechanism (5)
be reduced, by reducing a torque load on the drive source (2, 4).
According to this configuration, the control part (7) can limit the
negative torque of the transfer mechanism (5) without accompanying
the transmission operation of the transfer mechanism (5) with large
heat generation.
[0071] In addition, the vehicle drive device (3) of the present
embodiment includes a rotating electrical machine (4) provided in a
power transfer path between an output shaft (2a) of an engine (2)
and an input member (5a) of the transfer mechanism (5), and having
a rotating shaft (4a) drive-coupled to the input member (5a) of the
transfer mechanism (5), the rotating electrical machine (4) serving
as the drive source (2, 4), and the control part (7) can impose a
limitation that an absolute value of the negative torque of the
transfer mechanism (5) be reduced, by controlling at least one of
regeneration torque of the rotating electrical machine (4) and
output torque of the engine (2). According to this configuration,
the control part (7) can limit the negative torque of the transfer
mechanism (5) without accompanying the transmission operation of
the transfer mechanism (5) with large heat generation.
[0072] In addition, in the vehicle drive device (3) of the present
embodiment, the control part (7) sets a negative torque limiting
value which is a limiting value that limits an absolute value of
the negative torque, and reduces the negative torque limiting value
at a predetermined gradient when the control part (7) starts a
limitation that an absolute value of the negative torque of the
transfer mechanism (5) be reduced. According to this configuration,
compared to a case in which the negative torque limiting value is
suddenly reduced, a sudden reduction in braking force that
decelerates a vehicle (100) can be suppressed.
[0073] In addition, in the vehicle drive device (3) of the present
embodiment, in a state in which the control part (7) determines
that the oil pressure supplying part (6) is in the abnormal state,
when the control part (7) outputs an electrical instruction to the
oil pressure supplying part (6) to increase a flow rate of
lubricating oil supplied to the transfer mechanism (5), and
determines that a flow rate of lubricating oil supplied to the
transfer mechanism (5) from the oil pressure supplying part (6) has
increased as indicated by the electrical instruction, the control
part (7) considers that the oil pressure supplying part (6) has
been switched from the abnormal state to a normal state, and can
cancel a limitation that an absolute value of negative torque of
the transfer mechanism (5) be reduced. According to this
configuration, a braking force based on the drive source (2, 4) is
secured again, and driver's desired traveling can be
implemented.
[0074] In addition, in the vehicle drive device (3) of the present
embodiment, the control part (7) sets a negative torque limiting
value which is a limiting value that limits an absolute value of
the negative torque, and increases the negative torque limiting
value at a predetermined gradient when the control part (7) cancels
a limitation that an absolute value of the negative torque of the
transfer mechanism (5) be reduced. According to this configuration,
compared to a case in which the negative torque limiting value is
suddenly increased, a sudden increase in braking force that
decelerates the vehicle (100) can be suppressed.
[0075] In addition, in the vehicle drive device (3) of the present
embodiment, when the control part (7) imposes a limitation that an
absolute value of the negative torque of the transfer mechanism (5)
be reduced, the control part (7) outputs an electrical instruction
to a brake mechanism (13) that can brake the wheels (11), to
compensate for a braking force that decelerates a vehicle and that
is reduced by imposing the limitation, by increasing a braking
force of the brake mechanism (13).
[0076] According to this configuration, the control part (7) can
compensate for a braking force that decelerates the vehicle (100),
by increasing a braking force of the brake mechanism (13), and thus
can suppress a reduction in drivability.
INDUSTRIAL APPLICABILITY
[0077] A vehicle drive device according to the present disclosure
can be mounted on a vehicle, e.g., an automobile, and is suitable
for use in, for example, a hybrid vehicle of a single-motor
parallel system.
REFERENCE SIGNS LIST
[0078] 2: Engine (drive source), 2a: Output shaft, 3: Hybrid drive
device (vehicle drive device), 4: Motor/generator (drive source and
rotating electrical machine), 4a: Rotor shaft (rotating shaft), 5:
Transmission mechanism (transfer mechanism), 5a: Input shaft (input
member), 6: Oil pressure control device (oil pressure supplying
part), 7: ECU (control part), 11: Front wheel (wheel), 13: Brake
mechanism, and 100: Hybrid vehicle (vehicle)
* * * * *